Washer gain for timber structures formed of round wood poles



Sept. 11, 1956 K. c. JENNE 2,762,091

WASHER GAIN FOR TIMBER STRUCTURES FORMED OF ROUND WOOD POLES Filed April16, 1952 6 Sheets-Sheet 1 3nventor KENNETH 12.. LTENNB By 2 W GttornegSept. 11, 1956 K. c. JENNE WASHER GAIN FOR TIMBER STRUCTURES FORMED OFROUND WOOD POLES 6 Sheets-Sheet 2 Filed April 16, 1952 Imventor KENNETH13. LIENNE.

Gttomeg Sept. 11, 1956 K. C. JENN WASHER GAIN FOR TI Filed April 16,1952 MBER STRUCTURES FORMED OF ROUND WOOD POLES 6 Sheets-Sheet 5Isnvcntor KENNETH l1. QENNE Gttorneg Sept. 11, 1956 c; JENNE 2,762,091

WASHER GAIN FOR TIMBER STRUCTURES FORMED OF ROUND WOOD POLEIS f FiledApril 16, 1952 6 Sheets-Sheet 4 Inventor KENNETH B. TJENNE- interns;

Sept. 11, 1956 K. c. JENNE WASHER GAIN FOR TIMBER STRUCTURES FORMED OFROUND WOOD POL-ES 6 Sheets-Sheet 5 Filed April 16, 1952 ZSnventor (fttome Sept 11, 1956 K c JENNE WASHER GAIN FOR TIMBER STRUCTURES FORMED OFROUND WOOD POLE-S 6 shee ts-sheet 6 Filed April 16, 1952 JunentorKENNETH l1. JBNNE.

Gttomeg 2,762,09l Patented Sept. 11, 1956 WASHER GAIN FOR TIMBERSTRUCTURES FORMED F ROUND WOOD POLES Kenneth C. Jenne, Branford, Conn.,assignor to Malleahle Iron Fittings Company, Branford, Conn acorporation of Connecticut Application April 16, 1952, Serial No.282,618

3 Claims. (Cl. 2092) The present invention relates to washer gains andjoint assemblies for timber structures formed of round wood poles, asdistinguished from timber of rectangular cross-section. The use of roundwood poles as structural members is not new, for docks, trestles,bridges, and other similar structures, have been constructed from themfor years. Round poles have also been used as the crossarms for H-framestructures, such as are used for carrying transmission lines, but thisuse has been limited because the methods of fastening the poles eitherto each other or to other structural members have not generally beensuch as to withstand the loads imposed on such structures over longperiods.

While the present invention will find use in various timber structures,it is particularly suitable for H-frame, wish-bone frame, T-frame, andother similar line supporting structures, and the present disclosurewill be particularly directed to this type of structure.

While transmission line supporting frames, to a great extent, have beenconstructed of steel, the desirability of Wood for this purpose, andparticularly round wood poles, has been realized with increasinginterest within the past ten years or so. This interest results from anumber of factors:

1. During that period, steel has been in very short supply on manyoccasions.

2. Modern chemical treatments have greatly extended the useful life ofwood.

3. The initial cost of Wood structures is less than that of steel.

4. The maintenance of Wood structures is considerably less than steel,for example, no painting is required.

5. Wood, having considerable insulating property, permits a reduction inthe number of insulators used to support each conductor, thus resultingin considerable additional economy.

The basic problem in providing a fitting for connecting round poles isthat a round pole is used in its natural tapered shape, rather than amanufactured shape, and therefore, being a product of nature, itsperipheral characteristics vary widely, with the result that its actuaand nominal diameter at any given point may difier by as much as fiftypercent. In other words, a pole having a nominal diameter at a givenpoint of ten inches may, in fact, be considerably out of round so thatthe actual circumferential surface shape at the point of connectinganother pole thereto may be at substantial variance with a true ten inchdiameter pole. Additional variables are present in the form ofvariations in fiber strength, grain structure, etc.

While considerable development has taken place in the provision offixtures for finished timber of rectangular cross-section, there hasbeen very little development of such fixtures for round timber, probablybecause of the problem of adapting such fixtures to the variables commonto such round timber.

The general practise has been to fasten the round timbers together withone or more bolts, or with various considerably types of steel strapsand bands, both of which methods are inefiicient and costly. When tworound timbers are bolted together, stresses are concentrated on theprojected areas of the bolt holes causing a crushing of the fibersagainst the bolts and a deformation or bending of the bolt, andresulting in a combined shear, tension, and

deformation action upon the bolt, which is aggravated as the fibers ofthe wood surrounding the bolt become increasingly broken and crushed.

While the inherent strength of the wood pole is great,

the limitation in the past has been the inability of the fastening boltsor other connector means to provide sufficient strength to takeadvantage of the strength of the timber.

It is proposed in the present invention to provide an improved washergain designed to accommodate itself to gripping engagement with a roundsurface of a pole of a diameter and convex form having a large range ofvariation from a nominal given diameter, such washer gain being, ineffect, a transition piece which transmits the stresses imposed on thebolt over a large area of the round wood pole rather than through theprojected area of the bolt hole alone. It is particularly proposed toprovide means integral with the gain for transmitting such stresses overa large area in the form of cones, spurs and ribs.

It is a further object to provide an integral bolt hole engaging coneforming a bearing for the bolt, which cone is wedged into the end of thebolt hole so that the effective bearing area is increased whilepermitting of the use of a smaller diameter bolt. The economy in thesmaller bolt is made possible by the fact that the cooperative gaintransmits the load over a relatively large area of the pole thuseliminating the concentration of stresses which would otherwise beagainst the wood in line with the bolt hole. It is these stresses whichtend to split the pole.

Another object is to provide a washer gain adapted to cooperate with asimilar or companion washer gain in back-to-back relation so that thetwo gains may be engaged with crossing poles, and further to providesuch companion gains capable of rotation upon each other so that theycan be set at any desired angle, depending upon the crossing angle ofthe two poles.

It is further proposed to provide rotatable interlocking means upon thecompanion gains which, in addition to centering one upon the other forrotation, will minimize the shear stresses imposed on the bolt.

It is a further object to provide a washer gain for cooperation withother joint forming fittings designed to effect the butt jointing of theend of one pole to the side of another at various angles, certain ofsuch fittings permitting any desired variation in the angle, whileothers are designed for specific angles such as thirty degree, sixtydegree, etc. In every case, however, the cooperaitve washer gains are insuch relation to such fittings that the load strain is distributed overlarge areas of the poles so that the tendency for the Wood to split isminimized.

Other objects and advantages of the invention will become apparent froma consideration of the following detailed description taken inconnection with the accompanying drawings wherein satisfactoryembodiments of the invention are shown. However, it is to be understoodthat the invention is not limited to the details disclosed but includesall such variations and modifications as fall within the spirit of theinvention and the scope of the appended claims.

In the drawings:

Fig. l is a front elevation of a typical H-frame structure incorporatingthe washer gains and certain joint assemblies of the invention;

Fig. 2 is a side elevation thereof;

Fig. 3 is a rear elevation showing the inner or hole engaging side of awasher gain according to the invention;

Fig. 4 is a view partially in side elevation and partially in verticalsection, taken along the line 4-4 of Fig. 3;

Fig. 5 is a view partially in side elevation and partially in horizontalsection, taken along the line 55 of Fig. 3;

Fig. 6 is a front elevation of the washer gain illustrated in Fig. 3 andhaving a circular groove provided therein;

Fig. 7 is a similar view of a washer gain constituting a companion pieceto the gain as shown in Fig. 6, and having a circular rib for engagingthe circular groove of the gain as shown in Fig. 6;

Fig. 8 is a vertical sectional View showing a pair of companion gains inengagement with each other;

Fig. 9 is a rear elevation, similar to Fig. 3, and showing a gain havinga, larger area and adapted to accommodate a range of larger diameterpoles than the gain, as shown in Fig, 3;

Fig. 10 is a fragmentary front elevation of the gain as shown in Fig.9'and having a circular groove therein;

Fig. 11 is a similar view of a companion gain having a circular rib forengaging the circular groove of the gain as shown in Fig. 9;

Fig. 12 is a side elevation of a wedge shaped angle fitting for use informing a butt connection at a 30 angle;

Fig. 13 is a horizontal sectional view taken along the line 13-13 ofFig. 12;

Fig. 14 is an end view. of the angle fitting shown in Fig. 12, as seenfrom the right in Fig. 12;

Fig. 15 is a side elevation, partially in vertical section, of amodified form of fitting in which a member similar to that in Fig. 12 isprovided upon one face with anintegral washer gain structure;

Fig. 16 is a fragmentary side elevation of a modified form of anglefitting having a convex face;

Fig. 17 is a side elevation of anangle fitting for forming a buttconnection at a 60 angle, the dot-and-dash. lines showing modificationsthereof consisting of providing an integral washer gain structure uponone face and a convex.

surface upon the other face;

, Fig. 18 is an end elevation of the gain as seen from the rightin Fig.17;

Fig. 19 is arear elevation of the pole engaging. side of a modifiedwasher gain, particularly intended for forming a connection between twocrossing poles and a butt connection of another pole at anydesired'angle to the crossing poles;

Fig. 20 is a top end, view of the gain as shown' in Fig. 19;

Fig. 21 is a vertical sectional view takenalong the line 2121 of Fig.19;

Fig. 22 is a front elevation of. a linkconnector mem: ber forcooperative connection with the gain as seen in Fig. 19;

Fig. 23 is a vertical sectional view taken alongthe line 23-23 of Fig.22;

Fig. 24 is a front elevation of a connected'pole structure wherein anangular pole is crossed with and connected to a vertical pole and asecond angular pole is butt connected to the first angular pole, thelatter connection being effected by an angle fitting such as shown inFig. 17;

Fig. 25 is a view similar to Fig. 24in which the pole connectionsinclude a washer gain as shown in Fig. l9 in cooperation with a washergain as shown in Fig. 7 and a link connector as shown in Fig. 22;

Fig. 26 is a side elevation of the butt connection of the end of onepole to the side of another .pole, utilizing an angle fitting such asshown in Fig. 12;

Fig. 27 is a view partly in top plan and partly in horizontal section,taken alongthe line 27.27 of Fig. 1, and showing the-cooperative. use ofa pair of gains .of different sizes such as shown in Figs. 6 and 11; 7

Fig. 28 is a side elevation of a further modified form of connectorfitting for effecting an angle connection of the butt end of one polewith the side of another;

Fig. 29 is a top plan view thereof;

Fig. 30 is a top plan View of a modified form of connector link foreffecting the connection of a third pole to two crossing poles such asshown in Figs. 24 and 25;

Fig. 31 is a side view thereof;

Fig. 32 isa side elevation showing the connector fitting illustrated inFig. 28 connected to two poles; and

Fig. 33 is a side elevation showing the link illustrated in Fig. 30 inits connecting relation with a third pole connected to two crossingpoles.

Referring to the drawings, and more particularly to Figs. 3-6, thewasher gain illustrated therein and indicated generally as 10 isdimensioned so as to accommodate a range of pole diameters ofapproximately 6-10", it being understood that the invention contemplatesboth smaller and larger size gains to accommodate smaller and largerdiameter ranges. In. each case, howevencertain features are ofcorresponding size. and structure so that a gain of one size willcooperate with. a gain of the same or of another size, or with certainfittings, as will hereinafter more fully appear.

The gain 10 is of substantially square outline and the particular gainillustrated has a dimension along its sides of approximately 5 /3",although it will. be understood that this dimension may be varied underdifferent circumstances and is cited simply to indicate the comparativesize of the gain to the pole. The outer face 11 of the gain is flatwhile its inner face is concavely formed to sub stantially embrace theconvex curved surface of a pole.

To this end, the gain is provided with longitudinal side walls 1212between which extend a series of spaced ribs 13, the end ribs of whichconstitute the end walls of the gain. The edges of these ribs are shapedby forming their intermediate portions on a radius corresponding to theradius of the smallest diameter pole to be engaged, for instance 3", andextending the end portions of the edges in straight lines tangential'tothe curved intermediate portion so that increasing diameter poles willcontact these end portions between their ends andthe curved intermediateportion.

A series of longitudinal ribs 1'4v extends across the ribs 13 to form agrid-like structure with the upper edges of the ribsl4 flush. with theupper edges of'the ribs 13. Adjacent the side walls 12, the spacesbetweenthe ribs are open, as at 15, for the purpose of reducing weight,while the intermediate spaces are solid for added strength. A centralbolt-receivinghole 16 extends through the gain Withits axis normal tothe fiat outer face 11 and at its inner side is carried through, anannulusv 17 having an outer conical surface which, as shown in Fig.4,projects to a considerable extent from the convexly curved surfaces ofthe ribs.13. At each side of the holes 15, the ribs 13 are bevelal, asat 18, so that the end portions of the ribs may dig into the woodstructure of the pole with a wedging action, and between the ribs 13 theedges of, the end walls 12 are recessed, as at 19, so as to allow forthe better penetration of the ends of the ribs. into the wood surface.

Upon each of the end. ribs 13 constituting'the end walls the gain uponthe pole, but the stresses that are imposed upon the gain are notentirely concentrated'upon the spurs but are distributedthrough. theadditional widely distributed digging engagement of the. ribs, with the.pole.

The flat face of the gain 10 is provided. in concentric relation. with.thehole 16 with a circular groove 21 for the purpose of providing arotatable interlocking connecgreener 3 tion with a companion gain 22,illustrated in Fig. 7, which has a circular rib 23 formed upon its fiatface for engagement with the groove 21. The gain 22 is otherwiseidentical with the gain 10. The grooves 21 and the ribs 23 also providefor rotary interlocking engagement with other fittings, as willhereinafter more fully appear.

As shown in Fig. 8, the rib 23 is engaged with the recess 21 so that thecompanion gains are centered and may be rotated relative to each otherabout the axis of the bolt engaged through the holes 16. Thus, the poleon which one gain is mounted may be disposed at any desired angle to thepole upon which the other gain is mounted. In addition to centralizingthe gains for relative rotary movement, the rib and groove connectionserves to distribute stresses to both the poles and to minimize shearstresses on the bolt.

In Figs. 9 and 10 there is shown a modified form of gain 24 of a largersize to accommodate a larger range of pole sizes. In this case, theradius of the intermediate curved edge portions of the ribs 13 is largerthan the radius of the ribs of the gain 10, for instance 4" as comparedto 3", and the side dimensions are correspondingly increased. However,the gain 24 is provided with a similar size bolt hole 16 and with thesame size locking groove 21, so that it may be used as a companion gainwith the smaller gain 22 shown in Fig. 7. Similarly, a gain 25, Fig. 11,corresponding in size to the gain 24 is provided with a rib 23 so thatthis gain may be used as a companion gain with either the gain 24, orthe smaller gain 10 shown in Fig. 6.

The washer gains illustrated in Figs. 311 are employed as companionpairs in face-to-face relation in the connection of two poles incrossing relation with each other, the particular size of the gains forthe respective poles being determined by the approximate diameters or bythe actual peripheral curvature of the particular part of the pole wherethe connection is to be made. A typical application of the gains isshown in Figs. 1 and 2, illustrating an H-frame for transmission lines.Such frames are of substantial size being, for instance, 60' from theground to the top and 40' in width, and the poles employed may range indiameters from approximately to 6".

In practise, the frameis assembled fiat on the ground and then erectedinto its vertical position. The frame illustrated comprises two uprightpoles 26-26 supporting a horizontal spar pole 27 and having a pair ofcrossed brace poles 2828 connected between them at suitable pointsbetween the ground and the spar pole. The spar pole, which projects ateach end, normally supports the weight of insulators and thetransmission lines, and is, therefore, suitably trussed against bendingstrains by truss poles 30-30 and 31-31.

In this illustration, the points where the various poles cross eachother are connected in a similar manner through bolts and companionpairs of washer gains. The arrangement permits the connected poles to bedisposed at any desired angle to each other or, if occasion demands, inparallel relation.

A typical connection is shown in Fig. 27, wherein the part of theupright pole 26 at which the connection is made, is of relatively largediameter and has a large size gain 25, such as illustrated in Fig. 11,engaged therewith, while the bracing pole 28, being of smaller diameter,has the smaller size gain 10 as illustrated in Fig. 6 engaged therewith,these gains being selected so that one has a rib 23 and the other has aninterlocking groove 21.

Prior to assembly of the gains, the poles are provided with diametricbolt-receiving holes 32 which are of a size to loosely receive thethrough bolt 33. The face-toface gains are placed upon the respectivepoles with the cone projection 17 of each gain wedgingly fitted into therespective bolt hole and thereupon the bolt 33 is engaged through thetwo poles and has fitted upon its threaded ends curved washers 3434,which are retained thereon by nuts 35.

Upon tightening the nuts, the gains are drawn tightly into engagementwith the surfaces of the poles causing the spurs to become embeddedtherein and the rib surfaces of the gains to either firmly press againstthe surface of the pole or to become embedded therein, depending uponthe particular curvature of the pole surface. It should be pointed outin this respect that due to the natural shape of the pole, the curvaturemay vary at either side of the bolt hole, and due to the naturallongitudinal taper of the pole, the diameter at one end of the gain maybe slightly less than at the other end of the gain. The widelydistributed digging-in points of the spurs and ribs of the gain insure apositive interlocking engagement with the pole at sufliciently widelyspaced points as to provide maximum resistance to turning and slippage,as Well as to provide for the transmission of load stresses over a widearea of the pole.

It will be noted that the cone projection or annulus 17 is, in elfect, abearing thimble engaged in the end of the bolt receiving hole, and hasthe advantageous effect of a large diameter bolt, thus increasing theeffective diameter of the bolt at the point of shear represented by theinterface between the gain and the pole. It also supports the boltdirectly upon the gain rather than against the surface of the hole, sothat various forces applied to the bolt, which would otherwise tend tocrush the wood fibers and to split the pole, as well as to bend thebolt, will be transmitted through the gain to a large area of the pole.It is further pointed out that any tendency to split the pole isminimized by the fact that the body of the gain at each side of theannulus is in the shape of a wedge formation for disposition between thesurface of the pole and a load engaged with the bearing face of the gainand connected to the pole by the bolt extending through the annulus andthe pole.

It will also be noted that the stresses on both the poles are sodirected that the tendency to split or otherwise deteriorate the pole isminimized.

In the case of forming a butt connection of one pole with the side ofanother pole, several types of fittings may be employed in cooperationwith the washer gain. In the usual frame structure, the butt connectionsare at a definite angle, as, for instance 30 and 60, and for this typeof installation, it is preferred to provide a cooperative fitting havinga predetermined angle for use with the specific angle of the buttconnection.

In Figs. 1214 there is illustrated a 30 angle fitting, indicatedgenerally as 36, which comprises flat face walls 37-37, disposed at a 30angle to each other and connected by side walls 3838, the face wallsbeing braced intermediate their ends by connecting web portions 39 and40. The member 36 is symmetrical at each face side, and each face wallis provided with a slot 41 extending inwardly from one side edge to thecenter, the outer end of the slot being flared outwardly, as at 42, andthe side wall 38 having an opening 43 of suificient size to enable a nutcarried upon a bolt to be laterally moved into the slot from one side.In surrounding relation to the inner end of the slot, the inner side ofthe face Wall is provided with a rectangular rib formation 44 whichserves to receive the nut and hold it against turning, it being pointedout that the nut is backed off the thread of the bolt sufliciently toclear the rib formation as it is laterally moved into place, andthereupon it is drawn into the rib formation by pulling outwardly uponor tightening the bolt.

This arrangement enables an angle fitting to be assembled between a pairof poles after the bolts and Washer gains have been connected theretosimply by sliding the angle fitting sideways in between the poles. Thisfitting is employed in the illustration shown in Figs. 1 and 2, forconnecting the lower ends of the truss poles 30 and 31 to the spar pole27. The connection is illustrated in detail in Fig. 26, wherein it willbe seen that the 7 spar pole 27' has a gain zz connected thereto by athrough bolt 33, and similarly the truss pole- 30 has a; gain 22 securedthereto by a bolt'33, each of the bolts being provided atits outerendwith a curved washer 34 and a securing nut 35; and having securedupon its inner end a nut 46 disposed within the anglefitting.

Each of the face walls 37 is provided a circular groove 45- inconcentric relation to the inner end of the slot 4 1 andinterlo'ckin'gl'yreceiving theri'b' 23' of a cooperating washer gain.For convenience in manufacture, grooves are provided in the anglefitting, so that for cooperative engagement therewith, either a groovedain or 24; suchas shown in Figs. 6 and 10, maybe engaged therewith, inwhich case there will be no rotary interlocking, or a ribbed. gain 22 or25, such as shown in Figs. 7 and It, maybe interlockihgly engagedtherewith.

In Fig. l5 there is illustrated a modified form of angle fitting,generally indicated at 47, and which consists in providing one face ofan angle fitting. with an integral washer ain structure 48 ubs'tantial1ysimilar to the washer gain I0 shown in Figs". 3-6. The angle fitting'isotherwise similar to the fitting 36 shown in Fig. 12.

In Fig. l6 there is illustrated a further modification in.

which one face of the angle fitting, indicated generally at 49, andwhich is otherwise similar to either the angle fitting 36 illustratedin. Fig. 12, or the fitting 47 illustrated in Fig. is provided with aconv'exly formed face 50. This type of fitting may be used in caseswhere a pole has such a; bend or twist that its ends are. misaligned, sothat while one end may be connected at a definite angle, the other endis at an indeterminate angle. The convex surface 50', therefore, allowsthe flat face of the gain secured upon the truss ole to rock in anydirection upon the spherical convex surfacev to find its properposition.

As shown in Fig. 1, the butt connection of the truss ole 31 with theside of the truss pole 30. is at a 60 angle, and an angle fitting, asillustrated in Figs. 17 and 18, is empl yed at this point, itsconnection with the poles being illustrated in detail in Fig. 24. Thisangle fitting,

generally indicated as 51, comprises face walls 52 -52 disposed at anangle of 60 to each other, and side walls 53-53 extending between them.Each of the face walls is provided with a bolt receiving hole 54 and abearing portion 55 at the inner side. A pair of bracing ribs 5656extends between the intermediate portions of the face walls and are sospaced as to provide retainers for preventing the turning of the nutsengaged upon the bolts inserted through the holes 54 and bearing uponthe bearing portions 55'. It will be not'ed in this angle fitting thatthe extended axial line of the bolt hole 54' of one face wall will clearthe end of the other face wall, so that it is possible to engage thebolt straight through the holes from either side.

Each of the face walls 52 is provided with a circular groove 57concentric to the hole 54 for interlocking engagement of the circularribs of the washer gains. As shown in Fig. 24, the angle fitting 51 isconnected between the poles and 31 in asubst'antially similar mannor tothe securing of the fitting 36 as shown in Fig. 26, each of the polesbeing provided with washer gains 22, and the poles and gains beingconnected to the angle fitting by bolts 33 provided upon their outerends with curved washers 34 and nuts and upon their inner ends with nuts46 disposed against the inner sides of the face walls of the anglefitting.

In Figs. 19-23 there is illustrated a modifiedform of washer gai havinga connecting link member for cooperation therewith, particularlyintendedf'or connecta ing the buttend ofone pole to two crossing polesin substantially the same arrangement as. shown in Pig'24. The washer,gain. indicated generally at 58; consists of an upper part 59, generallysimilar to thewasher gain 10 as illustrated in Figs. 3-6, a towerintegrally formed part 60 of grid formation and somewhat narrower thanthe upper part 59, and angularly extending side arms 61'--61 each havinga bolt receiving bearing end provided with abolt' hole 62. The innerside of the lower portion 66 is curved in conformity to the curvature ofthe inner side of the upper portion 59 and constitutes, in effect, anextension thereof having ribs, recessed edges and spurs substantiallycorresponding in structure and arrangement to the corresponding parts ofthe upper part 59.

Because this fitting isintended to take heavy side strain along eitherone of the arms 61, the downward extension 60 provides auxiliary holdingmeans against relative turning upon the pole, and, additionally, thisextension is provided with a bolt hole 63 in which a bolt 64 is engagedas shown in Fig. 25. The'upper part 59 is provided with a circulargroove 65 for cooperative engagement of the circular rib 23 of either ofthe washer gains 22 or 25 used for eifecting the connection of the trusspole 30 to the upright pole 26.

The connection of the butt end of the pole 31 is made by means of achannel formconnector link 66, shown in Figs. 22 and 23, provided at oneend with a bolt hole 67 for connection with the arm 61 by means of abolt 68 as shown in Fig. 25, and provided at its other end with In Figs.28, 2'9 and 32, there is illustrated a modified form of link foreffecting the connection and angular relation of the butt end of a trusspole with the side of a spar pole or other similarly arranged pole. Thisconnection comprises a link 71 having a horizontal arm part 72 and anangular arm part 73 disposed at a desired angle to the part 72, as forinstance 30. Both arms are of channel form for reinforcement, the arm 72having the channel forming side walls 74 at its upper side and the arm73 having the channel forming walls 75 at its lower side.

The arm 72 is provided between the walls 74 with a thickened bearingportion 76 having a bolt receiving hole 77 therethrough and, inconcentric relation to'this hole, the underside of the arm 72 isprovided with a circular groove 78 for interlocking engagement of ,thecircular rib 23 of the washer gain 22 or 25, as shown in- Figs. 7 and11. The arm 73 is provided near its outer end with a bolt receiving hole79 and atits' upper side, and in concentric relation to the hole 79,there is provided a circular groove 80 for receiving the circular rib 23of a washer gain.

As shown in Fig. 32, the spar pole 27 and the truss pole 31 are providedwith washer gains 22 secured thereto by bolts 33 engaged through holes32 and, having curved washers 34 and nuts 35 upon their outer ends. Theinner ends of the bolts are respectively engaged in the bolt holes 77and 79 of the link and the assembly is secured by nuts 81-81 engagedupon the inner ends of the bolts and bearing respectively upon.thebearing portion 76 and upon the underside of the arm 73.

In Figs. 30, 31 and 33 there is illustrated a modified form of link forconnecting the butt end of a truss pole or the like in angular relationto a pair of crossed. poles, for instance one of the vertical poles 26of the H-frame and one of the truss poles 30. This connection consistsof a link 82 having a parallel sided armv portion 83 and a widened plateportion 84 extending from one end of the arm 83. The link is ofgenerally channel form for reinforcement, being provided with side walls85 extendirlg along the sides of the arm 83 and partially along thesides of the plate portion 84. Additional reinforce- 9 them ribs 86 areprovided partially along the side edges of the plate portion 84 at theopposite side from the walls 85.

The arm 83 is provided near its outer end with a bolt receiving hole 87,and in concentric relation to this hole there is provided on the forwardsurface a circular groove 88 for receiving the rib 23 of a washer gain.The plate portion 84 is of generally circular outline and is providedcentrally with a bolt receiving hole 89, and in each of its fiatsurfaces there is provided, in concentric relation to the hole, acircular groove 9% for receiving the rib of a washer gain.

As shown in Fig. 33, the poles 26 and 30 are connected by a through bolt33 having washers 34 and nuts 35 engaged upon its ends, washer gains 22being respectively provided upon the opposed sides of the poles. Insteadof being in face-to-face contact with each other, however, these gainshave the plate ends 84 of the link member 82 disposed between them, thebolt 33 extending through the bolt hole 89 thereof and the ribs 23 ofthe gains engaging the grooves 90. Thus, the link extends from theconnection of the poles 26 and 30 and may be disposed at any desiredangle, depending upon the angularity of the truss pole 31. This trusspole is provided with a washer gain 22 connected thereto by a throughbolt 33 having a curved washer 34 and a nut 35 engaged upon its outerend, the inner end of the bolt being engaged through the bolt hole 87and, secured by a nut 91 screwed upon its end and bearing upon therearward side of the arm 83.

What is claimed is:

l. A Washer gain for disposition between a round wood pole and a loadsupported by said pole, comprising a body having a forward sideincluding a load engaging forward bearing face of rectangular outline,said forward side having transverse end edges for disposition transverseto the pole axis and substantially parallel side edges for dispositionsubstantially parallel to the pole axis, a rearward side including apole conforming and engaging substantially cylindrical curved concaverearward surface, having its axis of curvature parallel to the plane ofsaid bearing face and coincident to the central vertical planeperpendicular to said heating face and midway between said side edges ofsaid forward side, said rearward side having transverse end edges fordisposition transverse to the pole axis and substantially parallel sideedges for disposition substantially parallel to the pole axis, end wallsextending between the respective end edges of said forward and rearwardsides, and side Walls extending between the respective side edges ofsaid forward and rearward sides, and means to effect an increasein theefiective diameter of the bolt at the point of shear represented by theinterface between the gain and the pole comprising an annulus disposedsubstantially centrally between said side edges of said rearward sideand projecting rea'rwardly therefrom and having an outer peripheral Wallin the form of a truncated cone, said body having a bolt receivingcylindrical passage having its axis coincident to said central plane andperpendicular to said bearing face and extending therefrom coaxiallythrough said annulus, the junction of the cylindrical Wall of saidpassage with the rearward end or said peripheral wall of said annulusforming a relatively sharp circular edge for wedging engagement of saidannulus in a bolt hole of said pole coaxial with and of substantiallythe diameter of said bolt receiving passage, said forward and rearwardsides and said end and side walls defining at each side of said centralvertical plane wedge formations for disposition between the roundsurface of a pole engaged by said concave rearward surface and a loadengaged with said bearing face and connected to said pole by a boltengaged through said respective bolt holes of said body and said pole.

2. A washer gain according to claim 1, further characterized by pairs ofpole engaging spurs projecting rearwardly from said rearward side, onepair being disposed adjacent each of said transverse end edges of saidrearward side, and the spurs of each pair being transversely spaced ateach side of said central vertical plane.

3. A washer gain according to claim 1, further characterized by a pairof link attaching arms respectively extending outwardly from each ofsaid side walls.

References Cited in the file of this patent UNITED STATES PATENTS1,786,991 Greim Dec. 30, 1930 FOREIGN PATENTS 100,476 Austria of 1925356,799 Great Britain Sept. 14, 1931 OTHER REFERENCES TECO Design Manualof 1943, page 2.

